This invention relates to a surgical instrument to apply a single hemostatic clip to a blood vessel or other internal tubular member. This invention also relates to a magazine tape containing a plurality of hemostatic clips which is contained in the surgical instrument. Finally, this invention relates to a method for applying a single hemostatic clip to a vessel or tubular member using the surgical instrument.
The Applicant is not aware of any prior art which in his judgment as a person having ordinary skill in the art anticipates or renders obvious the surgical instrument, magazine tape and method of this invention. However, to fully develop the background of the invention and to establish the state of the prior art, the following references are disclosed:
U.S. Pat. Nos. 3,837,555; and 3,650,453; and 3,086,208 teach the single injection of a surgical staple from a plurality of staples into disunited skin or fascia. In U.S. Pat. No. 3,837,555 and U.S. Pat. No. 3,650,453 the staples are contained in a flexible belt. The belt and the staples are contained in a cartridge which is adapted to be mounted on a powering instrument. The powering instrument has a power means, e.g. gas, which is used to develop rectilinear thrust against a piston. When the cartridge is mounted on the instrument, the piston thrust injects the staples into skin or fascia. Activation of the power means also causes the flexible belt to advance the next staple. U.S. Pat. No. 3,086,208 describes a manually operated skin clip applicator. A separate mechanical operation is necessary to advance the clips in the clip carrier, and to apply a single clip to skin or fascia.
A hemostatic clip applier marketed under the name Autostat.RTM. by Axiom Medical Inc., California, U.S.A. provides a plurality of clips in a cartridge. The cartridge is contained in the applier which is manually operated by a scissors handle. One of the scissor arms requires a cocking action to deliver the next clip into the jaws.
The surgical instrument described in this invention has advantages over the prior art. In a continuous advancement and retraction motion of a trigger pivotally mounted to a handle, the jaws of the surgical instrument compress the clip on the vessel, and then receive and maintain the next clip. The weight, size and mechanical advantage of the instrument is such that it can be manually held and continuously operated with one hand. The time between hemostasis can thus be reduced and the surgeon's other hand is available for other uses, e.g., locating and/or orienting a vessel which requires hemostasis.
The jaws of the instrument are offset to give the surgeon better vision in applying the clip to the vessel. In another advantage, as compared to single loading hemostatic clip applicators, the risk of improperly loading a clip and/or dropping the clip into a patient during a surgical operation or procedure is greatly reduced. In still another advantage, the jaws do not compress the hemostatic clip until the trigger is squeezed about two-thirds of its total motion. This differential allows for accidental squeezing of the surgical instrument by the surgeon or nurse without compressing the clip.
Another advantage is the clip positioning and feeding tabs on the magazine tape which maintain the hemostatic clip in the proper position in the jaws. Still another advantage is the magazine tape which prevents a dual delivery of clips into the jaws. Finally, the length of the magazine tape in relation to the length of the barrel is such that the end of the tape becomes visible at the proximal end of the barrel when the last clip is delivered to the jaws. This allows for a visual notification of the last hemostatic clip on the tape.
The surgical instrument of this invention applies a single hemostatic clip to a vessel. The instrument comprises a housing having a barrel and a handle. Jaws are attached to the distal end of the barrel to receive and maintain a hemostatic clip. Jaw cams are attached to the proximal end of the jaws. When not actuated, spring means hold the jaws in separation.
A jaw wedge is mounted adjacent to one side of the barrel. The distal end of the wedge has a rounded leading member and a slot. The proximal end of the wedge is adjacent to the proximal end of the barrel.
A feed bar is mounted adjacent to the opposite side of the barrel. The distal end of the bar has feed pawls and tabs. The proximal end of the bar is adjacent to the proximal end of the barrel.
A tape guide is attached to the barrel between the wedge and the bar. Each side of the guide contains a longitudinal recess. The distal end of the guide is adjacent to the jaws. The proximal end is adjacent to the barrel. A freely turning roller is attached to the distal end of the guide.
A magazine tape is integrally contained in the tape guide longitudinal recess adjacent to the jaw wedge. The initial end of the tape is wrapped around the tape guide roller and is contained by the feed pawls in the tape guide longitudinal recess adjacent to the feed bar. The tape contains a plurality of hemostatic clips.
A barrel end cover is adjacent to the distal end of the guide. The end cover contains a J-shaped leading member which protrudes over the roller, and a guiderail. The guiderail is adjacent to the distal end of the feed bar.
A trigger is pivotally mounted to the handle. When not actuated, spring means hold the trigger in separation from the handle. On completely squeezing the trigger, the rounded jaw wedge leading member advances into the jaw cams. The jaws are joined and the clip is compressed. On releasing the trigger, the jaws are opened. The jaw wedge slot then coordinates with the feed bar tab to advance the tape one pitch and deliver the next clip in the tape to the jaws.
In a preferred embodiment, the inside radius of the J-shaped leading member on the end cover is approximately equal to the radius of the roller plus the thickness of the magazine tape belt. In a more preferred embodiment, the guiderail contained on the end cover has sawtooth serrations adjacent the magazine tape.
In another preferred embodiment, the jaws are chanelled to receive and maintain the sides of the hemostatic clip in the jaws. In a more preferred embodiment, the distal end of the jaws are flanged to maintain the leading edges of the clip in the jaws. In a most preferred embodiment, the surgical instrument contains a magazine tape having feeding and positioning tabs which are adjacent to the apex of the clip and maintain the clip in the proper position for ligating in the jaws.
In yet another preferred embodiment, the jaw wedge leading member advances into the jaw cams after the trigger is squeezed about two-thirds of its total motion. In a more preferred embodiment, the jaw wedge slot on retraction coordinates with the feed bar tab to advance the tape one pitch, after the trigger is released about one-third of its total motion.
In a final preferred embodiment, the proximal end of the barrel has an opening to receive the initial end of the tape.
The magazine tape of this invention contains a plurality of hemostatic clips. The magazine tape comprises a flat flexible belt. A plurality of units are attached to the belt. Each unit contains a hemostatic clip. Each unit consists of in succession in parallel aligned pair of:
leading tabs; PA1 side retaining tabs and apex retaining tabs; PA1 and feeding and positioning tabs. PA1 inserting the surgical instrument described above into a body opening; PA1 placing the jaws around a vessel; and PA1 squeezing the trigger, whereby the jaws are joined and the clip is compressed.
The retaining tabs contain a groove adjacent to the sides of the belt. The groove has a height about equal to the thickness of a hemostatic clip. The groove has a thickness about equal to or less than the width of one side of a hemostatic clip. The portion of the apex tabs, which is adjacent to the apex of the clip, is contoured to accomodate the clip apex contour.
The feeding and positioning tabs have flanged upper portions. The flange is parallel with the longitudinal direction of the flat belt and extends away from the apex retaining tabs. The flange decreases in thickness away from the feeding and positioning tabs.
Each unit contains the leading ends of a hemostatic clip on the leading tabs and the sides and apex of a clip on the retaining tabs.
In a preferred embodiment, the thickness of the groove in the retaining tabs is contained inward from the side of the belt. In another embodiment, the flexible belt is composed of a polymeric material, e.g., polyurethane or polyethylene; or a laminated polymeric material. The laminated material can contain, e.g., paper and/or metal foil. In another preferred embodiment, the portion of the apex tabs adjacent to the clip apex is contoured to accomodate a V-shaped or a U-shaped clip apex. In still another preferred embodiment, the plurality of units is about equal to or less than 25.
The method of this invention comprises applying a single hemostatic clip to a vessel. The surgical instrument, and the preferred and more preferred embodiments of the surgical instrument described above are within the scope of this method. The method comprises:
In a preferred embodiment, the method comprises the additional step: releasing the trigger, whereby the jaws open and then the magazine tape is advanced one pitch so that the next clip in the tape is delivered to the jaws.